I do that too, specially when I need motivation or when I'm upset, thinking and reflecting about life. Although I'm not sure if it's a form of psychosis. When my pdoc asked me if I hear voices, I told him about this. Having to talk with my "imaginary friend" in my head. He said it might be psychosis as there is a spectrum of it. But till this day, he did not gave me a definite answer. But I'd like to think that this is normal It helped me at times when I was feeling lonely.